Arachidic acid is liberated in damaged, wounded, or inflamed tissues from phospholipids of cytoplasmatic membranes by the action of phospholipase enzyme and may be then metabolized by the cyclooxygenase cycle (by lipoxygenase enzyme) to prostanoids and eicosanoids. Antiphlogistics of both the steroid and nonsteroid nature, antibiotics, and sulfonamides are often used for therapeutic purposes. The antibiotics which specifically suppress pathogenic microbes and are often used in ophthalmology, are tetracycline, chloramphenicol, bacitracin, and neomycin. Therapeutics which prevent the development of inflammation (antiphlogistics) are both steroid and nonsteroid. The steroid antiphlogistics (e.g., dexamethasone block phospholipase. The anti-inflammatory drugs of nonsteroid nature (e.g., indomethacin, flurbiprofen, pirprofen) block cyclooxygenase and others. The blockage of these enzymes is important, because the products formed in metabolic cycles have a strong chemotactic effect (they cause accumulation of leukocytes in the sites of origin), (e.g., some leucotrienes) and increase the vascular permeability. This contributes to an excess development of the inflammation. Inflammations, (both of infectious and noninfectious origin) are very dangerous for the anterior and posterior segments of the eye. Thus, scars formed in the cornea during the final stage of the healing process cause the loss of an exceptional function of this tissue, i.e. transparency. The loss of transparency of optical media of the eye (cornea, lens) then leads to a reduction or even loss of sight.
A disadvantage of locally applied antiphlogistics is the relatively low efficiency, retarded healing, and contribution to the development of infection. The local effect of antibiotics is limited.
One of the very prospective possibilities of treatment is the inhibition of plasmin and other destruction proteases (e.g., collagenase or elastase) with specific inhibitors. These enzymes either directly develop the destruction processes (e.g., plasmin) or enable these processes by their own activity (e.g., collagenase, elastase). However, plasmin is effective not only as an initiator developing the degeneration processes proceeding in cascades, but also contributes to an excessive development of inflammation by several other mechanisms of which at least chemotaxis should be mentioned. U.S. Pat. Nos. 5,217,951; 5,290,762, and 5,190,917 which are herein incorporated by reference disclose the treatment of inflammation with serine protease inhibitors alone or in combination with a corticosteroid. None of the references teach or suggest eye and ear infections caused by parasites or relating to pseudomonas infection.
What is needed then is a medicamentous form for external use as an ophthalmologic or otolaryngologic drug.
This medicamentous form must have strong antiexudative, antiphlogistic, and antimicrobial effect. This medicamentous form is presenting lacking in the prior art.